Abstract: A toroidal transformer core topology having improved thermal and electrical properties has a two part core, one part concentrically disposed within the other, with the windings wound between the two. Less expensive materials and less material can be used to construct the core. The core can be constructed using inexpensive and efficient methods.

Abstract: An electronic converter converts high-voltage AC power main voltage, such as 120V, 240V or 277V, to a low-voltage suitable for driving a halogen lamp. The converter includes a rectifier circuit, starter circuit, a driver circuit, a current sensing circuit and a transformer circuit with an optional synchronous output rectifier. The current sensing circuit senses an output current of the converter. The sensed current is used to govern pulse-width modulation of the lamp drive voltage, to provide over-voltage protection. Temperature protection can also be provided to reduce drive current when the converter overheats. This enables reliable operation of the converter over an extended temperature range, and reduces the occurrence of converter component failures due to ground faults or overheating.